1. Field
Example embodiments relate to three-dimensional (3D) scene modeling, and more particularly, to a system and method for reliable wide range depth acquisition for a depth image.
2. Description of the Related Art
A Time-of-Flight (ToF) camera, a type of depth camera, has an advantage of providing depth information of a scene in real time, and thus is being used widely for various purposes, for example, human motion tracking, object modeling, and the like.
The ToF camera includes a light emitting device to emit an infrared ray light, for example, a light emitting diode (LED), and a sensor to detect the light. The ToF camera allows distance calculation by measuring a travel time taken by light to return to the sensor after bouncing off an object, as represented by Equation 1.
                    r        =                              ct                          time              ⁢                              -                            ⁢              of              ⁢                              -                            ⁢              flight                                2                                    [                  Equation          ⁢                                          ⁢          1                ]            
where r denotes a distance from an object, c denotes a speed of light, and ttime-of-flight denotes a travel time taken by light to return to a sensor after bouncing off the object.
Measuring a ttime-of-flight is difficult because the speed of light is exceptionally fast. To resolve this issue, ttime-of-flight is calculated in an indirect manner of measuring the intensity of light based on at least two different phases after frequency-modulated light is emitted. A further detailed description is provided with reference to FIG. 1.